Process of destructive distillation of resinous wood.



PATENTED OUT. 4, 1904.

v 0'. E. BROUGHTON. PROCESS OF DESTRUGTIVB DISTILLATION OP RESINOUS WOOD.

APPLICATION FILED JUIIE 13, 1904'.

N0 MODEL.

b .w i u w Ba 33% M W a "f P Roof;ss or-i bssisucrlve" msririnlon F nesiuogs w ofo SPEGI'I'E-ICATIQN forming part of Letters Patent No. 771,70 Application filed June 13,1904. serial No. 212,285 on meal.)

My process is intended especially to extract i 1 from resinouspine wood the spirits of turpentine, tar, tar-oil, pine-oils, creosote, pyrolig-' 'neous acid, pitch, and gas which theycontajn and to leave in the retort practicallypure I5 charcoal. By my process the several constituents are separately collected and turpentine as pure white spirits is obtained.- 4

The wood used in my process is obtained from the fallen or dead pine trees of the 11 Southern States, in which the resins-are conc'entrated in the trunk'aud limbs of the-trees.

These are. cut up into logs, blocks, chunks, or

' billets and charged into a retort to which superheated steam" at a pressure of-abo'ut sixty 5* pounds is admitted and with which the wood :2: is treated for a-period of about six hours until the readilyvaporizable or light 'oil of turpentineis distilled without becoming empyreumatica During this period weakly-acid 3' wateris also carried over with the turpentine,

\but all other constituents of the wood remain behind. The turpentine and weak .acid thus ":driven over are condensed and received in a Esuitable receptacle,- where the turpentine sep- =arates from the acid-water. A fire is then 'sta'rted beneath the retort and the temperaoff and it appears that the heavier tar-oils have the remainder of the turpentinef'is collected neous acid are separated and collected. in se is not necessarily boiled in this last step of the' the heiater maybe keptrsu ppliedwith enough:

commenced to distil', steamis shut off and the Patented October 4, 1204? 6, dated October 4;, 1904.1;

fire heat israised sufiicientlyjto fdrivefofl; all of the heavier oils, such as creosotefandlthe balance of the tar-oils. This treatment is eon-f tinned for about fourteenhou rs, wheni itwili -5 5 be found that practically pureiicharcoalpnly remains, the tar being drawnofi Ifrom-tiipe v to time as it collects in the bottom-of there: tort. The tar-oils are trapped and combined-- with the tar-oils previously' 'distilled,j vliile" 6O th'e-creosote-passes through the ondenser and is collected in a s'uitablereceiver;

It will thus be seen that practically; pure turpentinehaving no smeilof the; fire isob-Y tained during the first Estagefof the while during the secondfperiod en rapment which is only slightly" desolate-snaps slightly empyreumatic IDuriIigffthefirst and j second-periodsthe tar-oilsand weak pyr'oligf 7.

rate receptacles; During the -f-third: 1pc

nothing is added to the turpentinelprgvid distilled. While the creosote and'heavy agging are separated and collected. i As before stated, the turpentine obtamed'inl the. manner above described is-s'omewhat int-1 pure, and in order to obtain the-purewhitej; spirits it is subjected to further treatmentgf being firstrun' through a heater, from Wh'ich'f it passes to a still heated above the boiling point of water and preferably to that of tu'r-l pentiue. In this treatment the turpentin separated from the tar and creosote and l 1 other impurities which it contains, and it om 2 5 denses as pure white spirits. The turpentine;

process, as, preferably, a jet of wet 'ste'a'mis ad mitted from time to time to the still; xahiclif' as it passes ofi therefrom carriesover .gl f ules of turpentine mechanically" i'This-proc ess ofobtaining the pure white spirits of t ur pentine may. he carried on eontinpousbias,

(6o 9" indicates-the exhaust-pipe Fig; -2=s hows a transverse section of the retOIt'flHd its'furnace. Fig. 3' is ajdetail view of the steam-coil, employed in the still. Fig.-

:5 4'isa detail view of thepipe through which liveor wet steam is introduced into the still;

a The retort A may be of. any suitable construction. .P eferably it is located in a for nace B, the vi alls of which completely suraround the retort except at its front end, where it isprovided with adoor a. Two sets of grate-bars b are preferably employed, and the combustion-chambers 6' connect with a common chimney b. The fire is supplied 3 with fuel? through the doors 6. -:The retort is preferably made oval 'in cross-section and 9f ,gieuter-jlength than height. It inclines A a valved pipe '0, leading to a tar well or re eeptfacleG. Where a battery of retorts is employed, the receptacle C is preferably made in-the form of a trough, the tar being kept hohby & steam-piped. stealup'is'admitted into: the retort through iss apipe D, fitted with a valve 1. From the upperf ront 6nd ofthe retort extends a pipe which gas 'may.escape. Just beyond the tub,

is a trap K, which I 'events gas from passing beyond this-point. The coillempties into a receptaele'L, the flowof liquid thereto being .eolitr'olled by a valve- Z, This tank has a valved-outlet M at its lower end, and at its uppe it connects, by means of a pipe N, witha pump' O, Thelpipe N is provided with a valve-rt.- The pump 0 is connected by a pipeaB' with a heater Q,-.comprising a suitable casing-1" and a metallic'cylinder Q, which is tightly; The contents of the cylinder areheatedljya coil R, connecting with steamsupplypipes as shown. A draw-ofi cock q" is provided at the" bottom of the; cylinder Q, jand; thiscy-linder is connected, preferably mid 1-way between its upper and lower ends by 1 means of a valve-pipe R, 'with a still S, which is .simil'arin general construction tothe heater 5 5 .Q... It is provided with" a draw-oif cock 8 at its lojer end, and it is heated by a steam-coil Tat ltbe otthe'cylinder S and which connects. with the steam-supply pipes in the ma r own. 1

for the coil R, and 8" indicates the eirhaust-pipe for the, coil T. At its upper end the cylinder S is con- 'nected by a pipe U with a-fiondensing-coil V in a tub V, whichis supplied with cold water 5in any suitable way" The condensing=coil empties at its lower end into a receptacle. W, provided with a valved outlet X atitsjfupper .end and a draw-off cock Zat its lower end.

' The retort is preferably of a size suitable for acting on a cord of resinous wood at one time. a After the retort is charged steam is admitted thereto through the pipe I) at a temperature approximating 300 Fahrenheit. This treatment of the wood by steam is pref-. erably continued for about six hours, during which time the wood is softened and the readily vaporizable turpentine is driven ofi' through the connections above described and is received in the tank L. At the same time some weakly-acid water also passes 05- with the turpentine; but the latter is not rendered ,empyreuma'tic and .is practically pure, except that it. is mixed with pyroligneous water and condensed steam. This canbe readily separated in the tank L, the'condensed steam and pyroligneous water being drawn off through the cock M or all the turpentine which rises to the top being drawn off from above the water and pyroligneous water. I prefer, however, to

let the contents of the tank L remain there until the remainder of the turpentine has been distilled from the wood. This is done bythe second stage'of the process, in which steam at the same temperature is admitted to the retort and a fire is started up in the furnace, the temperature being raised to from 450 to 500? Fahrenheit, and this is co'ntinued'for about" I six hours, the wood being thus subjected to the combined action of steam and fire heat,

' which causes all of the remaining turpentine rooto be driven off and also the lighter tar-oils and some (a very little) creosote. The tar-oils are trapped in the drum F and pass down the pipe F into the receptacle G, while the turpentine and the small quantity of creosote that passes over with it is condensed and is received in the tank L, which then contains practically pure turpentine, except that it iscombined with a] small quantity-of creosote and some tar that passes over during the first and second periods of the distillation. The pyroligneous water and condensed steam can of course be'easily separated, but the creosote and tar cannot be separated until the turpen pine is further refined. While this stage of the process usually lasts over six hours, it is safestto test the distillate with a hydrometer,'.

and if this rises to, say, 92 this part of the process is discontinued. After the pyrolige neous water has been drawn ofl the pump 0 is put into operation 'and transfers the turpentine to the heater Q, which is kept at a temperature preferably of Fahrenheit. The turpentine maybe kept in this heater as long as desired and transferred to'the still as needed. After the receptacle L has been emptied the supply of steam is shut off. from the-retort and the fire heat is raised, preferably,to about 8009 Fahrenheit. This is continued forabout fourteen hours, 'andiduri'ng this stage of the process the remaining tarthe tar-oils already received in the receptacle G, while the creosote is condensed and enters the tank L, from which it may be withdrawn as it accumulates. From time to time during the process tar which accumulates in the bottom of the retort is drawn off through the pipe 0.

After the treatment above described, which usually lasts from twenty-six to thirty hours, it will be found that only charcoal remains in the retort. and when drawn from the retort easily crumbles. In order to refine the turpentine received in the heater Q. it is passed through the pipe R intothe still S, which is preferably heated to approximately the boilingpoint of turpentine, though it may be heated to a less deg ee. 1n the still the turpentine is separated from the creosote and tar or any other small quantities of impurities that it may contain and received in the receptacle W as pure white spirits of turpentine, mingled, of course, with water of condensation, which may be easily separated. As received in the tank Y the turpentine is ready for shipment. The tar, &c., maybe drawn off at s.

I find that muclr'better results are obtained by using a flat coil at the bottom of the still than a long one. such as used in the heater.

1 also find that by introducing live steam into the still the distillation of the turpentine is promoted and only a moderate amount of heat is necessary, as the turpentine is largely carried over mechanically by the steam as it passes out of the still. After the charge of wood in the retort has been thus distilled and the charcoal has been removed the retort is cleaned, preferably by jets of steam introduced into it, and then a new charge of wood is introduced and the process repeated in the manner before described.

By using a battery of retorts with suitable connections and using a single heater and still I can operate continuously only a portion of the contents of the heater being drawn into the still at any one time, and as the heater keeps the turpentine at relatively high temperature it does not tend to chill the still when entering it, and the vaporization of the tur pentine may be commenced promptly.

I claim as my invention 1. The process herein described for the destructive distillation of resinous wood, which consists in first treating the wood in a distil: ling-retort with superheated steam to drive of the easily-distilled light turpentine-oils with This is practically pure carbon and tar-oils thus driven off, then subjecting the wood to the action of fire heat alone at a higher temperature to drive oil? the creosote and heavy tar-oils, separately collecting the creosote and tar-oils thus driven oif, and from time to time drawing off tar from the retort whereby at the end of the treatment pure charcoal shall be left in the retort.

2. The process herein described for the destructive distillation of resinous wood which consists in first treating the wood in a distilling-retort with superheated steam at a temperature of approximately 300 Fahrenheit to drive off the easily-distilled light turpentineoils without rendering them empyreumatic, then subjecting the wood to the combined action of steam and fire heat at a temperature approximately of from 450 to 500 Fahrenheit to drive oif the remainder-of the turpentine and the light tar-oils, separately collecting the turpentine and tar-oils thus driven off. then subjecting the wood now deprived of all the turpentine-oils to the action of fire heat alone at a temperature of approximately 800 Fahrenheit to drive off the creosote and heavy tar-oils, separately collecting the creosote and tar-oils thus driven ofi, and from time to time drawing off tar whereby at the end of the treatment pure charcoal shall be left in the retort.

3. The process hereinbefore described for the destructive distillation of resinous wood which consists in first treating the wood in a distilling-retort with superheated steam injected at a temperature approximating the boiling-point of turpentine to drive off the easily-distilled light turpentine-oils without rendering them empyreumatic, then continuing the injection of steam and subjecting the wood to thecombined action of steam and fire heat at a higher temperature considerably above the boiling-point of turpentine to drive off the remainder of the turpentine and the light tar-oils, and separately collecting the turpentine and taroils thus driven off.

4. The process of extracting turpentine from wood containing it, which consists in subjecting the wood to superheated steam under pressure and at a temperature approximately the boiling-point of turpentine whereby the greater portion of the contained turpentine is extracted and volatilized, conducting ofi' and condensing the vapors, exposing the wood to steam raised to a higher pressure and a temperature considerably above the boiling-point of turpentine by the external application of flame, whereby the remainder of the turpen- CLARENCE ERNEST BROUGHTON.

Witnesses:

M. E.- 'Bmzenss, Gno. H. HAINES. 

